A team of researchers is hoping to better understand how noise from ship traffic could affect ringed seals in the Arctic.
William Halliday, a scientist at Canada’s Wildlife Conservation Society and an adjunct professor at the University of Victoria who researches underwater noise in the Arctic, was among two researchers who spent 10 days in Ulukhaktok last month.
He said the trip, where they mapped ringed seals’ habitat and recorded sounds they make, is the start of a four-year research project funded by Fisheries and Oceans Canada.
“Currently, there’s almost nothing known about how they change their behaviour or maybe even change their distribution when ships come by,” Halliday said, adding that ringed seals are a traditional food source for Inuvialuit and Inuit.
As sea ice continues to melt and ship traffic in the Arctic increases, Halliday said those changes could have impacts for wildlife like ringed seals.
Many marine mammals use sound to navigate, find food or mating partners, and monitor their environment. Research has found excess underwater noise can interfere with marine mammals’ ability to perceive sounds and lead to behavioural changes and increased stress. In extreme cases, it can lead to hearing loss and even death.
The Canadian government and environmental organizations have pushed for international measures to reduce underwater noise, particularly in Arctic waters.
Halliday said the research team in Ulukhaktok, who worked with the hunters and trappers’ committee and people from the community, counted 171 ringed seals. He said the seals tended to gather in groups around cracks in the ice where they would bask in the sun.
“We’d be driving across the ice and we’d see one seal off in the distance, and another seal in another direction off in the distance, and then suddenly we’d come across a group of 10 and we’d know right away that, at that group of 10, there must be a crack forming in the ice,” he described.
“It was really interesting to see how much they’re relying on the changes in the ice as the spring emerges and the water starts to open up a bit.”
In other cases, Halliday said, one to three seals would be located near breathing holes they had maintained in the ice.
In future years, Halliday said researchers plan to play ship noise using an underwater speaker. Based on the information they collected this year, he said they will likely target groups of seals gathered along cracks in the ice.
“It was really useful for next year’s study, when we’re back on the ice,” he said.
“There’s lots of water open so that we can get a speaker in the water, and get our hydrophones in the water, without disturbing the seal at their breathing hole.”